This grant is requested to support the writing, editing, printing, and distribution of the fourth edition of "Survey Report on Cerebrovascular Disease." The purpose of the Survey Report is to provide a succinct review of current status of various aspects of cerebrovascular disease, including pathology, clinical and laboratory examinations, special studies such as arteriography, treatment with reviews of surgery, anticoagulant therapy and other methods, and epidemiology. The Joint Council Subcommittee on Cerebrovascular Disease (National Institute of Neurologic Diseases and Stroke and National Heart and Lung Institute, NIH) has suggested that the Survey Report be brought up to date and has invited the applicant to act as editor. This subcommittee has authorized and published three previous editions. The first two were edited by Dr. James L. O'Leary and appeared July 1, 1961, and July 1, 1965. The third was edited by Dr. Robert G. Siekert, the current applicant, and appeared in July, 1971.